1. Field of The Invention
The subject invention relates to epoxy monomers suitable for the production of polymeric resins, methods for producing such epoxy monomers, and the resulting polymeric resins. The invention also generally relates to novel sucrose derivatives useful for preparing epoxy monomers and their polymerizable mixtures. Finally, the subject invention relates to articles coated with the epoxy resins, epoxy composites and the use of epoxy resins as adhesives.
2. Description of the Related Art
An epoxide, or oxirane, is a three membered ring (cyclic ether) containing two adjacent methylenes or methines and an oxygen. Epoxides are derivatives of ethylene oxide. Compounds containing epoxide groups are important because epoxides are highly reactive moieties that are useful starting materials for the synthetic chemist. In particular, epoxides are capable of being attacked by both electrophiles and nucleophiles. Epoxide chemistry is widely described in the literature such as in polymer chemistry texts and reviews (see, for example, Tanaka, Y. in Epoxy Resins: Chemistry and Technology, 2nd Edition, May, C. A. (editor), Marcel Dekker, New York, 1988, pp 9-284; Odian, G. Principles of Polymerization, 3rd Edition, J. Wiley & Sons, New York, 1991, pp 134-136; Stevens, M. P. Polymer Chemistry, 2nd Edition, Oxford University Press, New York, 1990, pp 329-351; and Bauer, R. S. in Epoxy Resins: Chemistry and Technology, A.C.S. Audio Course, American Chemical Society, Washington, D.C., 1991).
Commercial epoxy resins are oligomeric materials that contain one or more epoxy or oxirane group per molecule. The most widely used epoxy resins are the diglycidyl ethers of bisphenol-A obtained upon reaction of bisphenol-A with epichlorohydrin (see, May, C. A. in Epoxy Resins: Chemistry and Technology, 2nd Edition, May, C. A. (editor), Marcel Dekker, 2nd Edition, New York, 1988, pp 1-8).
Since their introduction in the late forties, epoxy resins have permeated many technologies. They are used extensively in adhesives, reinforced materials, and as coatings. As adhesives, epoxy resins are used to bind glass, wood, metals, and plastic surfaces. As coatings, because of their chemical resistance and excellent corrosion protection, they are used as primers in the maintenance of off- and on-shore refineries, chemical plants, off-shore drilling platforms, ships, automobiles, appliances and aircrafts. They also line drums, pails, food and beverage containers since they are chemically inert, non-toxic and impart no taste when fully cured. In structural applications, epoxy resins find use in potting and encapsulation of electrical equipment; adhesives for automobile and aircraft manufacturing; sealants in flooring and paving applications; grouting agents; and reinforced composites for the construction of pipes, tanks, aircraft and automobile components. These structural applications are possible because epoxy resins set quickly and have solvent and chemical resistance; low shrinkage upon cure; and excellent electrical, thermal and moisture resistance. However, they have some special storage and handling requirements (see, May, C. A. in Epoxy Resins: Chemistry and Technology, 2nd Edition, May, C. A. (editor), Marcel Dekker, 2nd Edition, New York, 1988, pp 1-8).
The glass transition temperature for epoxy resins cured with most standard curing agents tends to be low. This limits their usefulness in many applications. In addition, their manufacturing costs are high when compared with other crosslinked systems such as polyurethanes, phenol formaldehyde resins, urea formaldehyde resins and crosslinked polyesters. Therefore, there exists a need in the art for improved epoxy monomers which can be used for preparing epoxy polymers and resins. Moreover, given the various uses for epoxy polymers and resins, it is clear that improved epoxide monomers and polymers with better physical properties resulting from these methods are highly desirable. In addition to improved methods for producing epoxy monomers and polymers inexpensively, improved coated products, composites and adhesives comprising such epoxy monomers and polymers resulting from these methods would be highly desirable.